Desertification a quiet phenomenon - Essay Example

Desertification is the process where productive land degrades in numerous ways until it is no longer able to sustain vegetation. This phenomenon is a real threat to the health and livelihoods of millions of people all across the globe. The causes are numerous and complex, but almost always are the result of anthropogenic activity related to agricultural practices. Desertification is a quiet phenomenon, silently eradicating small farms and ranches and displacing entire communities, while larger, more media ready crises such as global climate change, nuclear contamination and ozone depletion seem to grab the headlines and legislative efforts of governments. Desertification needs to have the attention of the world for many reasons. The causes of desertification are largely preventable. Changes in agricultural practices are difficult because in many societies they are rooted in custom and culture. This fact, added to the economic advantage of exploiting marginal lands that are not claimed by any individual or even nation makes intervention difficult. Change is difficult, but not impossible. Education and economic incentives would go a long way towards changing human behaviors that contribute to desertification. Desertification needs to be addressed by the governments of the world on the grounds of social justice as well. Many affected and displaced by desertification are among the poorest in the world. In many cases, they live in societies that are not free and democratic. In these instances, their livelihoods are threatened by decision made by governments seeking to enrich national leaders at the expense of the poor. In societies ruled by power and patronage, the most helpless suffer for the unwise decisions of the powerful. Desertification needs to be addressed by the international community because it is a symptom of other dire societal ills. Nearly two billion people live in the areas that are in danger of desertification for one reason or another. Most of these people live in the developing countries. The geographic locations that are most susceptible to desertification are found in the marginal lands surrounding the world’s great deserts. Desertification usually brings to mind the Sahael region of Africa and the Caspian Basin in Asia. These are surely the most famous areas of desertification currently recognized in the world, but they are by no means the only areas suffering from this issue. The geographic expanse of this problem is indeed massive. Nearly 40% of the landmass on earth has a dry land climate. This means the areas are already desert or are at risk of desertification. The scientific cause of desertification is relatively simple. The mechanism causing the transformation of productive or stable soil into desert can be any of a number of things, but their end result is always the same. The process of desertification almost always begins with the removal of native grasses and other flora for the purposes of agricultural expansion. Sometimes drought follows the plough and other times it follows the hoof. The mechanical removal of native plants for the purpose of intensive cropping is the leading cause of desertification. The existing native flora does two things to keep the soil stable and productive. The plants growing in arid and semi-arid areas have adapted to the amount of precipitation and the timing of the precipitation available. This allows them to reproduce in the harsh environments found next to deserts. They have also developed root and branch systems that allow for the stabilization of native soils. Stabilization occurs when a healthy level of soil moisture is maintained and the soil is mechanically anchored and secured by the roots of native plants. The removal of native plants and the tilling of the soil destroy the symbiotic relationship between plants and soil in these fragile, arid ecosystems. The soil dries out because of its new exposure to the sun and the demands of the newly planted crops. Soil that gets too dry becomes too susceptible to wind erosion. Topsoil is notoriously thin in arid and semi-arid climates. This means that the productive life of a field that is plowed and cropped in an arid region may be limited to two or three years. After this, soil moisture is depleted and the topsoil has eroded away. In addition to the decrease in soil moisture, the destruction of the mechanical supports offered by native vegetation makes the arid soil even more susceptible to wind erosion. Crops, especially row crops, are not nearly as efficient as native plants at mechanically anchoring the soil. Cultivating fragile soils in semi-arid areas is a sure way to introduce desertification into once stable, fertile ecosystems. Another human activity that causes desertification to spread into fragile arid ecosystems is over-grazing by animals. This has a similar effect on the soil as tilling for crop production. Over-grazing leads to the removal of the native grasses from large swaths of natural pasture. The movement of the animal hooves churns the soil and helps it to dry out. Some grazing animals are more destructive in the way they eat as well. Sheep tend to pull grasses out by the roots while bovine animals tend to leave more of the roots behind. Stabilizing the natural pasture. While the overall effect may be similar when both over-grazing and plowing are done the root cause is quite different. Plowing and intensive cropping in semiarid regions is usually a state sponsored or corporate sponsored activity in the developing world. The cost of the machinery used to till the earth and in some cases provide irrigation is well beyond the reach of subsistence farmers. These massive agricultural schemes, with a focus on cash crops are destructive because of the sheer number of acres that can be cultivated and desertified in a short period of time. The motivation behind these activities is profit for the state or wealthy individuals. Over-grazing tends to be more influenced by the demands of culture and subsistence in the developing world. In many native cultures, everything from bride prices to fines for misconduct is paid in livestock. The measurement of wealth based on the amount of livestock owned has been a part of Sub-Saharan culture for millennia. The desire for cultural acceptance and recognition drives the decision by some farmers to over-graze their own lands, or to exploit lands that are unclaimed by individuals and unparallel by governments. Added to the cultural proclivity some groups have for raising livestock is the tenuous nature of subsistence farming in an arid land. Crop failures are frequent and rainfall is unpredictable in many of these regions. Livestock is a safeguard against famine if cash and staple crops fail for some reason. The drives between these two human activities are quite different, but the results are almost identical. The final source of human induced desertification is diversion if water for massive irrigation schemes. In arid and semi-arid regions, many soils are capable of safe and sustainable agricultural production with the proper amount and management of irrigation. Indeed, many of the most productive lands around the world can be found in wealthy nations that were able to divert water onto fields for cropping in semi-arid regions. The ancient Sumerians began this in Mesopotamia and the practice has continued right up through modern times in places such as the Imperial Valley in California. But poorly managed irrigation schemes can contribute to the spread of desertification as much as cropping or over-grazing. Irrigation contributes to desertification in two ways. One way is by diverting water that is bound for inland bodies of water such as Lake Chad in Africa or the Aral Sea in Asia. These inland bodies of water depend on inflow from rivers that have their head in more humid climates. The feeding of water into the lake is essential for the lake to maintain its shoreline. The high rate of evaporation in these arid climates means that if the flow of water to the lake is interrupted or decreased, then the level of water will begin to lower. The shoreline will recede and desert land will be exposed. The salinity of the water leaves salts behind that render the newly exposed land unsuitable for farming or pasturage. It is in every way a desert. The second way irrigation can add to desertification is through salinization of once productive soils. Arid climates evaporate much of the irrigation water unless it is administered in significant quantities and through a very efficient delivery system. When the irrigation water evaporates, the salts and minerals suspended in the water are deposited in the soil. This decreases soil fertility and eventually results in the salinization of the entire irrigated area. One method of overcoming salinization in soils is to thoroughly flush the soil with an abundance of irrigation water. This method however will exacerbate further desertification downstream from the irrigation scheme. An overarching reality of desertification is the fact that these destructive human activities are actually made worse by the cyclical nature of climate and precipitation in arid and semi-arid regions. Cyclical weather and climate patters result in the settlement and utilization of pastures and farms that geologically are very young and whose lifespan is tenuous. An example of these phenomena can be found in the Sahael region south of the Sahara desert. The Sahael is a band of semi-arid land that borders the Sahara to the south and west. Unusually wet seasons for several decades in the 1800’s actually saw the width of the Sahael region grow. The Sahara seemed to be in retreat for several generations. As new settlements were made in this newly cultivatable area, pressures from traditional grazing and cropping began to tax the fragile eco-system. Desertification began as a result of human activity in the 1950’s and quickly accelerated in the 1970’s when rainfall returned to a more geologically typical level. As a result, the Sahara began to spread over areas that were once cultivated. Many pointed to the fact that his was a natural cycle of increasing and decreasing precipitation, but his mattered little when the images of human displacement and suffering were sent by the media around the world. A new focus on anthropogenic desertification was realized, but was short lived because the crisis ended and the world focus went on to other crises. The suffering and displacement realized in the Sahael region of Africa in the 1970’s is a good example of desertification caused by a combination of human activity and cyclical climate patterns. Many attempts have been made to stem desertification over the years. Planting trees as windbreaks and to secure dry soils was a popular effort through the 1980’s and 1990’s. The problem with this effort was the fact that it took a lot of time and money to nurture the trees to adulthood. Subsistence farmers had neither the time nor the money to sustain the tree planting efforts. Many of the efforts of this type failed as well because the young trees were used for fuel. Recent efforts to construct windbreaks have centered on using native woody plants. In the Sahael, farmers are being trained in methods that allow them to prune native shrubs in a way that encourages upward, shady growth and root development. Rows of these plants are used to deaden winds around pastures and fields. The pruned waste from each tree can be sued as mulch to retain moisture in the soil or to be burned as fuel. Other solutions are not so easily had. Changing culture is a very difficult thing to do. As a result, overgrazing for cultural reasons continues all around the world. Also of note is the role poverty plays in desertification. Economic diversity may hold the key to halting desertification in some places. Subsistence agriculture still dominates areas where desertification, but non-productive enterprises such as ecotourism are starting to take hold. This takes some of the pressure off of the land and allows it to bb regenerated through remediation efforts. The solutions to desertification are as varied as are the causes that drive this economic issue. With international attention and plenty of effort, the ravages of desertification can largely be halted and reversed. Bibliography Glantz, Michael H. Drought Follows the Plow. Cambridge: Cambridge UP, 1994. Print. Read More